Spleen 30.09.2020

1. . Which of the following statements regarding splenic anatomy is true?

The splenic ligaments are all avascular.

The tail of the pancreas is often contained in the splenorenal ligament.

The average weight of the adult spleen is 300 g.

The first branches of the splenic artery are the short gastric arteries.

Accessory spleens are most commonly found in the greater omentum.

Although the majority of the splenic ligaments are in fact avascular, the gastrosplenic ligament contains the short gastric vessels. Additionally, in the case of portal hypertension, other splenic ligaments may become vascularized.
The tail of the pancreas may be injured during splenectomy because it often lies within the splenorenal ligament.
The average weight of the adult spleen is 150 g (range, 75 to 300 g).
The first branches of the splenic artery are the pancreatic branches and then the short gastric, the left gastroepiploic (which may also give rise to the short gastric arteries), and the terminal splenic branches. The splenic artery divides into segmental branches that enter the trabeculae of the spleen. There are two types of anatomy of the splenic artery: the distributive and magistral types. The distributive subtype is much more common (70% of individuals) and is characterized by a short splenic artery trunk and multiple long branches entering the spleen. Conversely, the magistral type has a long main trunk that divides relatively near the hilum. Accessory spleens are common, especially in patients with hematologic disorders, and are found in 15% to 35% of patients. In decreasing order of frequency, they are found in the splenic hilum, the gastrosplenic ligament, the splenocolic ligament, the splenorenal ligament, the greater omentum and mesentery, and the left pelvis along the left ureter or by the left testis or ovary, but they have been identified anywhere within the peritoneal cavity.

Explanation

Although the majority of the splenic ligaments are in fact avascular, the gastrosplenic ligament contains the short gastric vessels. Additionally, in the case of portal hypertension, other splenic ligaments may become vascularized.
The tail of the pancreas may be injured during splenectomy because it often lies within the splenorenal ligament.
The average weight of the adult spleen is 150 g (range, 75 to 300 g).
The first branches of the splenic artery are the pancreatic branches and then the short gastric, the left gastroepiploic (which may also give rise to the short gastric arteries), and the terminal splenic branches. The splenic artery divides into segmental branches that enter the trabeculae of the spleen. There are two types of anatomy of the splenic artery: the distributive and magistral types. The distributive subtype is much more common (70% of individuals) and is characterized by a short splenic artery trunk and multiple long branches entering the spleen. Conversely, the magistral type has a long main trunk that divides relatively near the hilum. Accessory spleens are common, especially in patients with hematologic disorders, and are found in 15% to 35% of patients. In decreasing order of frequency, they are found in the splenic hilum, the gastrosplenic ligament, the splenocolic ligament, the splenorenal ligament, the greater omentum and mesentery, and the left pelvis along the left ureter or by the left testis or ovary, but they have been identified anywhere within the peritoneal cavity.

2. A 10-year-old boy is hit by a truck while riding his bicycle home from school. A CT scan shows a tear of the spleen. His hematocrit is 32%, and he is in pain, although fully alert and oriented. His blood pressure is 110/60 mm Hg, and his heart rate is 104 bpm. The next step in management should be which of the following?

Cross-match blood and transfuse appropriately

Perform splenectomy as soon as possible

Perform laparotomy, and suture the tear where possible.

Perform angiographic embolization of the spleen

Avoid surgery, even if bleeding continues profusely after transfusion

The risk of infection after removal of the spleen as well as the good results of conservative treatment should encourage a nonoperative approach in children. In adults, surgery is usually recommended, but when possible, the spleen should be repaired and not removed. If the spleen is to be removed on an elective basis,pneumovax and prophylactic vaccine against H. influenza are given about 2 weeks before surgery.

Explanation

The risk of infection after removal of the spleen as well as the good results of conservative treatment should encourage a nonoperative approach in children. In adults, surgery is usually recommended, but when possible, the spleen should be repaired and not removed. If the spleen is to be removed on an elective basis,pneumovax and prophylactic vaccine against H. influenza are given about 2 weeks before surgery.

3. A 55-year-old individual has a history of a splenectomy following a motor vehicle accident as a child. The patient now comes to the physician about other complaints. This patient:

Has decreased susceptibility to infection with malarial parasites and Bartonella species.

Is likely to require vaccination against Haemophilus influenzae, Streptococcus pneumoniae, and meningococci.

Is subject to an increased risk for infection and should have been vaccinated at least 1 month before splenectomy.

Requires revaccination every 10 years.

Should be vaccinated with the newest 14-valent vaccine against S. pneumoniae.

The spleen has the ability to clear unopsonized bacteria and microorganisms for which the body has no antibodies.
It can clear organisms contained within erythrocytes (such as malaria and Bartonella species); thus, an asplenic individual is more susceptible to these infections. Individuals who have undergone splenectomy are more susceptible to infection with encapsulated organisms, especially H. influenzae, S. pneumoniae, and meningococci.
If preoperative vaccination is possible, administration should be undertaken at least 2 weeks before splenectomy for optimal antibody response.
For patients undergoing emergency splenectomy, vaccines should be given 2 weeks postoperatively or at the time of hospital discharge if the patient is deemed unlikely to comply with follow-up care.
The recommended reimmunization interval for pneumococcal and meningococcal vaccines is 5 years, not 10 years. The benefit of revaccination for H. influenzae is unclear.
A 23-valent pneumococcal vaccine is now used for immunization.

Explanation

The spleen has the ability to clear unopsonized bacteria and microorganisms for which the body has no antibodies.
It can clear organisms contained within erythrocytes (such as malaria and Bartonella species); thus, an asplenic individual is more susceptible to these infections. Individuals who have undergone splenectomy are more susceptible to infection with encapsulated organisms, especially H. influenzae, S. pneumoniae, and meningococci.
If preoperative vaccination is possible, administration should be undertaken at least 2 weeks before splenectomy for optimal antibody response.
For patients undergoing emergency splenectomy, vaccines should be given 2 weeks postoperatively or at the time of hospital discharge if the patient is deemed unlikely to comply with follow-up care.
The recommended reimmunization interval for pneumococcal and meningococcal vaccines is 5 years, not 10 years. The benefit of revaccination for H. influenzae is unclear.
A 23-valent pneumococcal vaccine is now used for immunization.

4. A 38-year-old man undergoes excisional biopsy of a cervical lymph node. Pathology reveals Hodgkin's lymphoma. Which of the following statements about Hodgkin's disease is TRUE?

Splenectomy is always required for accurate staging.

Staging laparotomy involves liver biopsy, biopsy of the spleen, and periaortic lymph node dissection.

Stage II disease involves disease on both sides of the diaphragm.

If the spleen is involved, the patient has stage IV disease.

Splenectomy is sometimes indicated for thrombocytopenia is not an absolute indication of splenectomy

Option 6

Staging of Hodgkin’s disease is often done nonoperatively. Staging laparotomy consists of wedge biopsy of the liver, splenectomy, examination and biopsy of preaortic lymph nodes, as well as biopsy of mesenteric and hepatoduodenal nodes. Stage I Hodgkin’s lymphoma is limited to one anatomic area, while Stage II involves 2 or more areas of the same side of the diaphragm. Stage III disease involves both sides of the diaphragm limited to lymph nodes, Waldeyer’s ring or the spleen. Stage IV disease involves organs other than lymph nodes, Waldeyer’s ring, or the spleen. Splenectomy may improve thrombocytopenia and allow chemotherapy to be administered.

Explanation

Staging of Hodgkin’s disease is often done nonoperatively. Staging laparotomy consists of wedge biopsy of the liver, splenectomy, examination and biopsy of preaortic lymph nodes, as well as biopsy of mesenteric and hepatoduodenal nodes. Stage I Hodgkin’s lymphoma is limited to one anatomic area, while Stage II involves 2 or more areas of the same side of the diaphragm. Stage III disease involves both sides of the diaphragm limited to lymph nodes, Waldeyer’s ring or the spleen. Stage IV disease involves organs other than lymph nodes, Waldeyer’s ring, or the spleen. Splenectomy may improve thrombocytopenia and allow chemotherapy to be administered.

5. A 5-year-old child with sickle cell anemia who underwent splenectomy several months earlier following a sequestration crisis is now being evaluated because of several days of fever and fatigue after exposure to a sick contact at school. When he arrives at the emergency department, he is hypotensive, tachycardic, and lethargic. Which of the following is true about his current condition?

The incidence is lower when splenectomy is performed for hematologic disease.

The incidence is highest within 6 months of splenectomy.

Patients require lifelong antibiotic prophylaxis, usually with penicillin, especially those older than 5 years.

Mortality rate approaches 90%.

Complications include peripheral gangrene, deafness, and endocarditis.

Overwhelming post-splenectomy infection (OPSI) is a life-threatening disorder that must be recognized promptly and treated appropriately. Typically, it manifests as a prodromal phase of 1 to 2 days of nonspecific symptoms such as sore throat, malaise, myalgias, diarrhea, vomiting, fevers, and chills. This situation can progress rapidly to hypotension, disseminated intravascular coagulation, respiratory distress, and death. Mortality rates may exceed 50%, and it is often complicated by severe sequelae such as those in choice E. The incidence of OPSI is higher following splenectomy performed for hematologic disorders and in younger patients. OPSI may occur at any time following splenectomy, although the incidence is highest within the first 2 years after splenectomy. Daily prophylactic penicillin therapy for asplenic patients remains controversial. The main reason for prophylaxis is to decrease the incidence of OPSI. The duration of and need for therapy have been contested, although many advocate prophylaxis for 3 to 5 years, especially in younger children undergoing splenectomy.

Explanation

Overwhelming post-splenectomy infection (OPSI) is a life-threatening disorder that must be recognized promptly and treated appropriately. Typically, it manifests as a prodromal phase of 1 to 2 days of nonspecific symptoms such as sore throat, malaise, myalgias, diarrhea, vomiting, fevers, and chills. This situation can progress rapidly to hypotension, disseminated intravascular coagulation, respiratory distress, and death. Mortality rates may exceed 50%, and it is often complicated by severe sequelae such as those in choice E. The incidence of OPSI is higher following splenectomy performed for hematologic disorders and in younger patients. OPSI may occur at any time following splenectomy, although the incidence is highest within the first 2 years after splenectomy. Daily prophylactic penicillin therapy for asplenic patients remains controversial. The main reason for prophylaxis is to decrease the incidence of OPSI. The duration of and need for therapy have been contested, although many advocate prophylaxis for 3 to 5 years, especially in younger children undergoing splenectomy.